Tetrahydropthalimide compounds, and their production and use as herbicides

ABSTRACT

A tetrahydrophthalimide compound of the formula: ##STR1## wherein R 1  is hydrogen, alkyl, lower cycloalkyl, lower alkyl (lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl (lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R 2  is hydrogen, lower alkyl or lower alkoxy, X is chlorine or bromine, Y is oxygen or imino and Z is oxygen or sulfur, which is useful as a herbicide.

This application is a continuation of copending application Ser. No. 887,970 filed on Jul. 21, 1986 now U.S. Pat. No. 4,770,695 which is a continuation of application Ser. No. 445,726, filed on Nov. 30, 1982, now abandoned.

The present invention relates to tetrahydrophthalimide compounds, and their production and use.

The said tetrahydrophthalimide compounds (hereinafter referred to as "tetrahydrophthalalimide(s)") are representable by the formula: ##STR2## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is hydrogen, lower alkyl or lower alkoxy, X is chlorine or bromine, Y is oxygen or imino and Z is oxygen or sulfur.

In the above significances, the number of carbon atoms in the alkyl group is not more than 12. The term "lower" is generally intended to have not more than 8 carbon atoms, preferably 3 to 7 carbon atoms for a cyclic moiety and not more than 6 carbon atoms for a non-cyclic moiety. Preferred numbers of carbon atoms for lower alkyl, lower cycloalkyl, lower alkenyl, lower cycloalkenyl and lower alkynyl are respectively from 1 to 6, from 3 to 7, from 2 to 6, from 5 to 6 and from 2 to 6. Preferable numbers of carbon atoms for lower alkoxy, lower alkylthio, lower alkylideneamino and lower cycloalkylideneamino are respectively from 1 to 6, from 1 to 6, from 1 to 6 and from 3 to 7. More preferably, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, halo(lower)alkyl and lower cycloalkylideneamino represented by R₁ may be respectively C₃ -C₇ cycloalkyl, C₁ -C₂ alkyl(C₃ -C₆)cycloalkyl, C₃ -C₆ cycloalkyl(C₁ -C₂)alkyl, C₁ -C₄ alkoxy(C₁ -C₄)alkyl, C₂ -C₄ alkenyl, C₅ -C₆ cycloalkenyl, C₅ -C₆ cycloalkenyl(C₁ -C₂)alkyl, cyano(C.sub. 1 -C₃)alkyl, C₃ -C₄ alkynyl, C₁ -C₄ alkylideneamino, C₁ -C₄ alkylthio(C₁ -C₄)alkyl, halo(C₁ -C₄)alkyl and C₄ -C₆ cycloalkylideneamino; and lower alkyl and lower alkoxy represented by R₂ may be respectively C₁ -C₃ alkyl and C₁ -C₂ alkoxy.

It is known that some tetrahydrophthalimide compounds exhibit a herbicidal activity. For instance, U.S. Pat. No. 3,984,435, EP 0049508A, U.S. Pat. No. 4,032,326, etc. disclose that 2-(4-chlorophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione, 2-[4-chloro-3-(1-propylthiocarbonylbutoxy)phenyl]-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione, 2-(4-chloro-2-fluoro)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione, etc. are useful as herbicides. However, their herbicidal effect is not always satisfactory.

It has now been found that the tetrahydrophthalimides (I) show a strong herbicidal activity against a wide variety of weeds by foliar or soil treatment in plowed fields. Advantageously, some of them do not produce any material phytotoxicity on agricultural crops (e.g. corn, soybean, cotton). Their herbicidal activity is particularly notable on post-emergence foliar treatment of broad-leaved weeds such as common purslane (Portulaca oleracea), common lambsquarters (Chenopodium album), redroot pigweed (Amaranthus retroflexus), hemp sesbania (Sesbania exaltata), velvetleaf (Abtilon theophrasti), prickly sida (Sida spinosa), ivyleaf morningglory (Ipomoea hederacea), tall morningglory (Ipomoea purpurea), field bindweed (Convolvulus arvensis), jimsonweed (Datura stramonium), black nightshade (Solanum nigrum), cocklebur (Xanthium pensylvanicum), sunflower (Helianthus annus), common ragweed (Ambrosia artemisifolia) in corn or soybean fields as they do not afford any toxicity to corn or soybean. Likewise, they exhibit a good herbicidal activity against Graminaceous weeds such as barnyardgrass (Echinochloa crus-galli), broad-leaved weeds such as false pimpernel (Lindernia procumbens), toothcup (Rotala indica) and waterwort (Elatine triandra) and paddy field weeds such as nutsedge (Cyperus serotinus), monochoria (Monochoria vaginalis) and arrowhead (Sagittaria pygmaea) in paddy rice fields, while exerting no significant damage to rice plants. Accordingly, they can be used as herbicides applicable to paddy fields as well as agricultural plowed fields. They are also useful as herbicides to be employed for orchards, pastures, lawns, forests, non-agricultural fields, etc.

Among the tetrahydrophthalimides (I) of the invention, favorable are those of the formula (I) wherein R₂ is hydrogen or lower alkyl. More favorable are those of the formula (I) wherein R₂ is hydrogen or methyl. Most favorable are those of the formula (I) wherein R₂ is hydrogen as they show a high selectivity to soybean or corn by foliar treatment.

The tetrahydrophthalimides (I) can be produced by reacting a HY-phenyltetrahydrophthalimide of the formula: ##STR3## wherein X and Y are each as defined above with an α-halo-carboxylic acid ester of the formula: ##STR4## wherein A is chlorine or bromine and R₁, R₂ and Z are each as defined above in a solvent in the presence or absence of a dehydrohalogenating agent, usually at a temperature of 0 to 200° C. for 1 to 240 hours. The amounts of the α-halo-carboxylic acid ester (III) and the dehydrohalogenating agent may be respectively 1.0 to 10 equivalents and 0.5 to 1.5 equivalents to the HY-phenyltetrahydrophthalimide (II). When desired, a phase transfer catalyst such as tetrabutylammonium bromide or benzyltributylammonium chloride may be employed.

As the solvent, there may be used an aliphatic hydrocarbon (e.g. hexane, heptane, ligroin, petroleum ether), an aromatic hydrocarbon (e.g. benzene, toluene, xylene), a halogenated hydrocarbon (e.g. chloroform, carbon tetrachloride, dichloroethane, chlorobenzene, dichlorobenzene), an ether (e.g. diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, diethylene glycol dimethyl ether), a ketone (e.g. acetone, methylethylketone, methylisobutylketone, isophorone, cyclohexanone), an alcohol (e.g. methanol, ethanol, isopropanol, t-butanol, octanol, cyclohexanol, methylcellosolve, diethylene glycol, glycerol), a nitrile (e.g. acetonitrile, isobutyronitrile), an acid amide (e.g. formamide, N,N-dimethylformamide, acetamide), a sulfur compound (e.g. dimethylsulfoxide, sulfolane), water, etc. They may be employed alone or in combination.

Examples of the dehydrohalogenating agent are an organic base (e.g. pyridine, triethylamine, N,N-diethylaniline), an inorganic base (e.g. sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydride), an alkali metal alkoxide (e.g. sodium methoxide, sodium ethoxide), etc.

The produced tetrahydrophthalimide (I) is, when desired, purified by a per se conventional procedure such as chromatography or recrystallization.

The starting HY-phenyltetrahydrophthalimide (II: Y=NH) can be produced by treating a nitrophenyltetrahydrophthalimide of the formula: ##STR5## wherein X is as defined above with 2.0 to 10 equivalents of an iron in the presence of an acid in a solvent (e.g. acetic acid, water, methanol, ethanol, tetrahydrofuran) at a temperature of 20 to 100° C.

The production of the nitrophenyltetrahydrophtalimide (IV) is summarized in the following scheme: ##STR6## wherein X is as defined above.

Namely, the haloaniline (V) is treated with 1.0 to 1.5 equivalents of conc. nitric acid in conc. sulfuric acid at a temperature of 10 to -10° C. to give the nitroaniline (VI), which is then reacted with 3,4,5,6-tetrahydrophthalic anhydride in a solvent (e.g. toluene, xylene, acetic acid, propionic acid, water, dioxane) at a temperature of 0 to 200° C., whereby the nitrophenyltetrahydrophthalimide (IV) is obtained.

The thus obtained compound (IV) may be subjected to usual work-up or, if necessary, to purification by chromatography or recrystallization.

The starting HY-phenyltetrahydrophthalimide (II: Y=O) can be produced as well by reacting a phenol of the formula: ##STR7## wherein X is as defined above according to the following scheme: ##STR8## wherein X is as defined above.

Namely, the hydroxyphenyltetrahydrophthalimide (II') can be manufactured from the phenol (VII) by nitrating the same, reducing the resultant nitrophenol (VIII) and reacting the resulting aminophenol (IX) with 3,4,5,6-tetrahydrophthalic anhydride.

Conversion of the phenol (VIII) into the nitrophenol (VIII) may be accomplished by application of a per se conventional nitration procedure to the former. Usually, however, the indirect nitration which consists of the following three steps is favorable in achievement of the selective nitration at the desired position: ##STR9## wherein X is as defined above. Thus, the phenol (VII) is converted into its alkali metal salt by treatment with an aqueous solution of an alkali metal hydroxide (e.g. sodium hydroxide, potassium hydroxide), and the resulting salt is reacted with an alkyl haloformate such as methyl chloroformate in water at a temperature of 0 to 10° C. The thus prepared carbonic ester (X) is nitrated with a mixture of conc. sulfuric acid and conc. nitric acid at room temperature. Then, the nitrobenzene (XI) thus obtained is hydrolyzed with an aqueous alkaline solution such as an aqueous sodium hydroxide solution at a temperature of 20° to 120° C. to give the nitrophenol (VIII).

Conversion of the nitrophenol (VIII) into the aminophenol (IX) may be accomplished by any per se conventional reduction procedure for changing a nitro group to an amino group. Examples of such reduction procedure are catalytic reduction, reduction with iron powder, reduction with sodium sulfide, reduction with sulfurated sodium borohydride, etc. For instance, treatment of one molar amount of the nitrophenol (VIII) with a 3 molar amount of hydrogen in the presence of a 1/10 to 1/100 molar amount of platinum dioxide in an inert solvent (e.g. ethanol, ethyl acetate) at room temperature under atmospheric pressure affords the aminophenol (IX). Further, for instance, treatment of one molar amount of the nitrophenol (VIII) with a 2 to 5 molar amount of iron powder such as reductive iron or electrolytic iron in a 5% acetic acid solution or a dilute hydrochloric acid solution at a temperature of 80° to 100° C. for a period of 1 to 5 hours produces the aminophenol (IX).

For production of the hydroxyphenyltetrahydrophthalimide (II') from the aminophenol (IX), the latter is reacted with 3,4,5,6-tetrahydrophthalic anhydride in an inert solvent (e.g. acetic acid) while refluxing for a period of 1 to 6 hours, preferably of 2 to 4 hours.

In any event, the phenol (VI) is known (cf. Finger et al.: J.Am.Chem.Soc., 81, 94 (1959)).

Practical and presently preferred embodiments for production of the tetrahydrophthalimides (I) as well as the intermediary compounds are illustratively shown in the following Examples.

EXAMPLE 1

2-(4-Chloro-2-fluoro-5-hydroxyphenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione (3 g) was dissolved in dimethylformamide (100 ml), and anhydrous potassium carbonate (0.8 g) was added thereto. To the resultant mixture was added methyl bromoacetate (1.8 g), and the mixture was heated at 70°-80° C. for 3 hours. After being allowed to cool, water was added to the mixture, which was then extracted with ether, and the extract was washed with water, dried and concentrated. The residue was purified by silica gel column chromatography to give 1.3 g of 2-(4-chloro-2-fluoro-5-methoxycarbonylmethoxyphenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione (Compound No. 1). M.P., 98°-99.5° C.

EXAMPLE 2

2-(3-Amino-4-bromo-6-fluorophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione (0.85 g) was dissolved in 1,4-dioxane (5 ml), and ethyl bromoacetate (3.3 g) was added thereto. The resultant mixture was refluxed for 6 hours. Triethylamine (0.2 g) was added thereto, and the mixture was refluxed for 1 hour. After being allowed to cool, water and toluene were added to the mixture, which was then extracted with toluene. The toluene layer was dried and concentrated. The residue was purified by silica gel column chromatography to give 1.0 g of 2-(4-bromo-2-fluoro-5-ethoxycarbonylmethylaminophenyl)-4,5,6,7-(tetrahydro-2H-isoindole-1,3-dione (Compound No. 89). n_(D) ²⁶.0 1.5281.

Examples of the tetrahydrophthalimides (I) produced by the same procedure as above are shown in Table 1.

                                      TABLE 1                                      __________________________________________________________________________      ##STR10##                                           (I)                       Compound No.                                                                           X  Y     Z  R.sub.1         R.sub.2  Physical constant                 __________________________________________________________________________     1       Cl O     O  CH.sub.3        H        M.P. 98-99.5° C.           2       Cl O     O  CH.sub.2 CH.sub.3                                                                              H        n.sub.D.sup.21.5 1.5441           3       Cl O     O  CH.sub.2 CH.sub.2 CH.sub.3                                                                     H        n.sub.D.sup.14.5 1.5414           4       Cl O     O                                                                                  ##STR11##      H        n.sub.D.sup.14.5 1.5413           5       Cl O     O  (CH.sub.2).sub.3 CH.sub.3                                                                      H        M.P. 70-73° C.             6       Cl O     O                                                                                  ##STR12##      H        n.sub.D.sup.21.5 1.5351           7       Cl O     O  C(CH.sub.3).sub.3                                                                              H        n.sub.D.sup.14.5 1.5376           8       Cl O     O   (CH.sub.2).sub.4 CH.sub.3                                                                     H        M.P. 90-91° C.             9       Cl O     O                                                                                  ##STR13##      H        n.sub.D.sup.18 1.5321             10      Cl O     O  (CH.sub.2).sub.5 CH.sub.3                                                                      H        n.sub.D.sup.26 1.5321             11      Cl O     O  (CH.sub.2).sub.11 CH.sub.3                                                                     H        n.sub.D.sup.22.5 1.5176           12      Cl O     O                                                                                  ##STR14##      H        n.sub.D.sup.16 1.5431             13      Cl O     O                                                                                  ##STR15##      H        M.P. 100-101° C.           14      Cl O     O                                                                                  ##STR16##      H        n.sub.D.sup.17.0 1.5619           15      Cl O     O                                                                                  ##STR17##      H        n.sub.D.sup.18 1.5378             16      Cl O     O                                                                                  ##STR18##      H        n.sub.D.sup.18 1.5401             17      Cl O     O                                                                                  ##STR19##      H        n.sub.D.sup.16.5 1.5345           18      Cl O     O                                                                                  ##STR20##      H        n.sub.D.sup.14.0 1.5439           19      Cl O     O                                                                                  ##STR21##      H        n.sub.D.sup.15.0 1.5513           20      Cl O     O                                                                                  ##STR22##      H        n.sub.D.sup.15.5 1.5418           21      Cl O     O  CH.sub.2 CH.sub.2 OCH.sub.3                                                                    H        n.sub.D.sup.20 1.5440             22      Cl O     O  CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 CH.sub.3                                                  H        n.sub.D.sup.19 1.5275             23      Cl O     O  CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 CH.sub.2                                  CH.sub.3        H        n.sub.D.sup.21.5 1.5358           24      Cl O     O                                                                                  ##STR23##      H        n.sub.D.sup.19 1.5402             25      Cl O     O  CH.sub.2 CH.sub.2 CH.sub.2 OCH.sub.3                                                           H        n.sub.D.sup.21.5 1.5429           26      Cl O     O                                                                                  ##STR24##      H        M.P. 102-103° C.           27      Cl O     O  CH.sub.2 CH.sub.2 SCH.sub.2 CH.sub.3                                                           H        n.sub.D.sup.18 1.5395             28      Cl O     O  CH.sub.2 CH.sub.2 CN                                                                           H        n.sub.D.sup.20  1.5507            29      Cl O     O  CH.sub.2 CH.sub.2 F                                                                            H        n.sub.D.sup.20.5 1.5476           30      Cl O     O  CH.sub.2 CH.sub.2 Cl                                                                           H        n.sub.D.sup.15 1.5496             31      Cl O     O  CH.sub.2 CHCl.sub.2                                                                            H        M.P. 105-107° C.           32      Cl O     O  CH.sub.2 CF.sub.3                                                                              H        n.sub.D.sup.15 1.5205             33      Cl O     O  CH.sub.2 CH.sub.2 CH.sub.2 Cl                                                                  H        M.P. 71-72° C.             34      Cl O     O                                                                                  ##STR25##      H        n.sub.D.sup.20.5 1.5490           35      Cl O     O                                                                                  ##STR26##      H        M.P. 82-84.5° C.           36      Cl O     O                                                                                  ##STR27##      H        n.sub.D.sup.22.5 1.5597           37      Cl O     O                                                                                  ##STR28##      H        n.sub.D.sup.23.5 1.5500           38      Cl O     O  CH.sub.2 CF.sub.2 CF.sub.2 H                                                                   H        n.sub.D.sup.24 1.5156             39      Cl O     O  CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 Cl                                                         H        M.P. 80-82.5° C.           40      Cl O     O  CH.sub.2 CH.sub.2 Br                                                                           H        n.sub.D.sup.15.5 1.5611           41      Cl O     O  CH.sub.2 CHCH.sub.2                                                                            H        n.sub.D.sup.16 1.5615             42      Cl O     O                                                                                  ##STR29##      H        n.sub.D.sup.17 1.5412             43      Cl O     O                                                                                  ##STR30##      H        n.sub.D.sup.17.5 1.5345           44      Cl O     O                                                                                  ##STR31##      H        n.sub.D.sup.23.5 1.5572           45      Cl O     O                                                                                  ##STR32##      H        n.sub.D.sup.18 1.5470             46      Cl O     O                                                                                  ##STR33##      H        n.sub.D.sup.16.5 1.5568           47      Cl O     O                                                                                  ##STR34##      H        n.sub.D.sup.16 1.5421             48      Cl O     O                                                                                  ##STR35##      H        n.sub.D.sup.17.5 1.5589           49      Cl O     O                                                                                  ##STR36##      H        n.sub.D.sup.16.0 1.5707           50      Cl O     O  CH.sub.2 CCH    H        M.P. 91-91.5° C.           51      Cl O     O  CH.sub.3        CH.sub.3 M.P. 57.1° C.              52      Cl O     O  CH.sub.2 CH.sub.3                                                                              CH.sub.3 n.sub.D.sup.21.0 1.5399           53      Cl O     O  CH.sub.2 CH.sub.2 CH.sub.2 Cl                                                                  CH.sub.3 M.P. 60-64° C.             54      Cl O     O  (CH.sub.2).sub.4 CH.sub.3                                                                      CH.sub.3 n.sub.D.sup.26 1.5241             55      Cl O     O                                                                                  ##STR37##      CH.sub.3 M.P. 108-113° C.           56      Cl O     O  CH.sub.2 CH.sub.3                                                                              CH.sub.2 CH.sub.2 CH.sub.3                                                              n.sub.D.sup.21.0 1.5254           57      Cl O     O  CH.sub.3        OCH.sub.3                                                                               n.sub.D.sup.24 1.5391             58      Cl O     O                                                                                  ##STR38##      OCH.sub.3                                                                               n.sub.D.sup.24.5 1.5268           59      Cl O     O  (CH.sub.2).sub.4 CH.sub.3                                                                      OCH.sub.3                                                                               n.sub.D.sup.25.0  1.5294          60      Cl O     O                                                                                  ##STR39##      OCH.sub.3                                                                               n.sub.D.sup.27.5 1.5401           61      Cl O     O                                                                                  ##STR40##      OCH.sub.3                                                                               n.sub.D.sup.24.5 1.5272           62      Br O     O  (CH.sub.2).sub.3 CH.sub.3                                                                      H        n.sub.D.sup.23.5 1.5376           63      Br O     O                                                                                  ##STR41##      H        n.sub.D.sup.19 1.5448             64      Br O     O  CH.sub.2 CH.sub.2 OCH.sub.3                                                                    H        n.sub.D.sup.20 1.5475             65      Br O     O  CH.sub.2 CH.sub.2 Cl                                                                           H        n.sub.D.sup.17.0 1.5593           66      Br O     O                                                                                  ##STR42##      H        n.sub.D.sup.18 1.5504             67      Cl O     S  CH.sub.2 CH.sub.3                                                                              H        M.P. 116-119° C.           68      Cl O     S                                                                                  ##STR43##      H        n.sub.D.sup.26 1.5531             69      Cl O     S  CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.3                                                            H        M.P. 82-84° C.             70      Cl O     S  CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.3                                          H        M.P. 97-100° C.            71      Cl O     S                                                                                  ##STR44##      H        M.P. 127-129° C.           72      Cl O     S  CH.sub.2 CHCH.sub.2                                                                            H        M.P. 145-147° C.           73      Cl O     S                                                                                  ##STR45##      H        n.sub.D.sup.24 1.5811             74      Cl O     S                                                                                  ##STR46##      H        M.P. 147-150° C.           75      CL O     S  CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.3                                                   CH.sub.3 n.sub.D.sup.25 1.5314             76      Cl O     S  CH.sub.2 CH.sub.2 CH.sub.3                                                                     C.sub.3 H.sub.7 (n)                                                                     n.sub.D.sup.25.5 1.5319           77      Br O     S  CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.3                                                   H        M.P. 81-84° C.             78      Cl NH    O  CH.sub.2 CH.sub.3                                                                              H        n.sub.D.sup.28 1.5519             79      Cl NH    O                                                                                  ##STR47##      H        n.sub.D.sup.24.5 1.5445           80      Cl NH    O                                                                                  ##STR48##      H        n.sub.D.sup.25 1.5401             81      Cl NH    O                                                                                  ##STR49##      H        Glassy                            82      Cl NH    O                                                                                  ##STR50##      H        n.sub.D.sup.25 1.5466             83      Cl NH    O  CH.sub.2 CHCl.sub.2                                                                            H        Glassy                            84      Cl NH    O                                                                                  ##STR51##      H        M.P. 119-120° C.           85      Cl NH    O  CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 CH.sub.3                                                  H        n.sub.D.sup.25 1.5364             86      Cl NH    O  CH.sub.2 CH.sub.2 CN                                                                           H        n.sub.D.sup.25 1.5541             87      Cl NH    S  CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.3                                                   H        n.sub.D.sup.24 1.5621             88      Cl NH    O  CH.sub.3        CH.sub.3 Glassy                            89      Br NH    O  CH.sub.2 CH.sub.3                                                                              H        n.sub.D.sup.26 1.5281             90      Br NH    O  CH.sub.2 CH.sub.2 OCH.sub.3                                                                    H        M.P. 106-107° C.           91      Br NH    O   CH.sub.3       CH.sub.3 n.sub.D.sup.24.5 1.5661           92      Br NH    O                                                                                  ##STR52##      OCH.sub.3                                                                               n.sub.D.sup.24.5 1.5596           93      Cl O     S  CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.3                                                   H        M.P. 87-88° C.             94      Cl O     O  H               H        M.P. 148.5-150°            __________________________________________________________________________                                                  C.                           

EXAMPLE 3 Production of the HY-phenyltetrahydrophthalimide (II: X=Cl; Y=NH)

A solution of N-(4-chloro-2-fluoro-5-nitrophenyl)-3,4,5,6-tetrahydrophthalimide (16.2 g) in acetic acid (200 ml) was dropwise added to a suspension of iron powder (14 g) in a 5% aqueous acetic acid (30 ml) at 90°-100° C. and refluxed for 1 hour. After being allowed to cool, chloroform was added to the resultant mixture, followed by filtration. The organic layer was separated from the filtrate, washed with a saturated sodium hydrogen carbonate solution, dried and concentrated. The residue was recrystallized from a mixture of ether and petroleum ether to give 7.5 g of N-(3-amino-4-chloro-6-fluorophenly)-3,4,5,6,-tetrahydrophthalimide. M.P., 144.5°-146.5° C.

EXAMPLE 4 Production of the HY-phenyltetrahydrophthalimide (II: X=Br; Y=NH)

In the same manner as in Example 3 but using N-(4-bromo-2-fluoro-5-nitrophenyl)-3,4,5,6-tetrahydrophthalimide in place of N-(4-chloro-2-fluoro-5-nitrophenyl)-3,4,5,6-tetrahydrophthalimide, there was produced N-(3-amino-4-bromo-6-fluorophenyl)-3,4,5,6-tetrahydrophthalimide. M.P., 163°-164.5° C.

EXAMPLE 5 Production of the HY-phenyltetrahydrophthalimide (II: X=Cl; Y=O)

2-Chloro-4-fluoro-5-aminophenol (6.6 g) and 3,4,5,6-tetrahydrophthalic anhydride (6 g) were dissolved in acetic acid (20 ml) and refluxed for 2 hours. The resultant mixture was allowed to cool to room temperature and poured into ice-water, followed by extraction with ether. The ether extract was washed with a saturated sodium hydrogen carbonate solution and water in order, dried over anhydrous magnesium sulfate and concentrated. The residue was purified by silica gel chromatography to give 4.0 g of N-(4-chloro-2-fluoro-5-hydroxyphenyl)-3,4,5,6-tetrahydrophthalimide. M.P., 151° C.

NMR (CDCl₃, D₆ -DMSO) δ (ppm): 1.5-2.0 (4H, m), 2.1-2.6 (4H, m), 6.8 (1H, d, J=6Hz), 7.15 (1H, d, J=10Hz).

IRν^(nujol) _(max) (cm⁻¹): 3380, 1680.

EXAMPLE 6 Production of the HY-phenyltetrahydrophthalimide (II: X=Br; Y=O)

In the same manner as in Example 5 but using 2-bromo-4-fluoro-5-aminophenol in place of 2-chloro-4-fluoro-5-aminophenol, there was produced N-(4-bromo-2-fluoro-5-hydroxyphenyl)-3,4,5,6-tetrahydrophthalimide. M.P., 167°-168° C.

NMR (CDCl₃, D₆ -DMSO) δ (ppm): 1.5-2.0 (4H, m), 2.1-2.7 (4H, m), 6.8 (1H, d, J=6Hz), 7.25 (1H, d, J=10Hz).

IRν^(nujol) _(max) (cm⁻¹): 3380, 1690.

EXAMPLE 7

Production of the nitrophenyltetrahydrophthalimide (IV: X=Cl)

4-Chloro-2-fluoro-5-nitroaniline (19 g) and 3,4,5,6-tetrahydrophthalic anhydride (15.2 g) were dissolved in acetic acid (50 ml) and refluxed for 6 hours. After being allowed to cool, the resultant mixture was poured into water and extracted with toluene. The toluene layer was washed with water, an aqueous sodium hydrogen carbonate solution and water in order, dried and concentrated. The residue was crystallized from ethanol to give 20 g of N-(4-chloro-2-fluoro-5-nitrophenyl)-3,4,5,6-tetrahydrophthalimide. M.P., 157°-157.5° C.

EXAMPLE 8 Production of the nitrophenyltetrahydrophthalimide (IV: X=Br)

In the same manner as in Example 7 but using 4-bromo-2-fluoro-5-nitroaniline in place of 4-chloro-2-fluoro-5-nitroaniline, there was produced N-(4-bromo-2-fluoro-5-nitrophenyl)-,3,4,5,6-tetrahydrophthalimide. M.P., 155°-156° C.

EXAMPLE 9 Production of the nitroaniline (VI: X=Br)

To a solution of 4-bromo-2-fluoroaniline (58.6 g) in conc. sulfuric acid (100 ml), there was dropwise added a mixture of conc. nitric acid (25.3 g) and conc. sulfuric acid (15 ml) at a temperature of 0° to -5° C. The resultant mixture was stirred at 0°-5° C. for 1 hour, poured into ice-water and extracted with toluene. The toluene layer was washed with water and an aqueous sodium hydrogen carbonate solution and concentrated. The residue was purified by silica gel chromatography to give 16.4 g of 4-bromo-2-fluoro-5-nitroaniline. M.P., 90°-92° C.

EXAMPLE 10 Production of the nitroaniline (VI: X=Cl)

In the same manner as in Example 9 but using 4-chloro-2-fluoroaniline in place of 4-bromo-2-fluoroaniline, there was produced 4-chloro-2-fluoro-5-nitroaniline. M.P., 83°-84.5° C.

EXAMPLE 11 Production of the nitrophenol (VII: X=Cl)

2-Chloro-4-fluorophenol (83.4 g) was added to a solution of sodium hydroxide (27.7 g) in water (450 ml), and methyl chloroformate (69.2 g) was dropwise added thereto at a temperature below 10° C. Precipitated crystals were collected by filtration and washed with water to give methyl (2-chloro-4-fluorophenyl) formate (134.8 g). M.P., 69°-71° C.

Methyl (2-chloro-4-fluorophenyl) formate (134.8 g) obtained above was suspended in conc. sulfuric acid (50 ml). To the suspension, a mixture of conc. sulfuric acid (50 ml) and conc. nitric acid (50 ml) was added at about 30° C., and the mixture was stirred for 1 hour at this temperature. The reaction mixture was poured into ice-water, and precipitated crystals were collected and washed with water. Methyl (2-chloro-4-fluoro-5-nitrophenyl) formate (143 g) was thus obtained. M.P., 53°-55° C.

The product obtained as above was combined with sodium hydroxide (27 g) and water (300 ml), and the resultant mixture was refluxed for 4 hours. Precipitated insoluble materials were filtered using a celite, and the filtrate was acidified with conc. hydrochloric acid. Precipitated crystals were collected by filtration and washed with water to obtain 76.3 g of 2-chloro-4-fluoro-5-nitrophenol. M.P. 106°-107° C.

NMR (CDCl₃, D₆ -DMSO) δ (ppm): 7.25 (1H, d, J=10Hz), 7.64 (1H, d, J=6Hz).

IRν^(nujol) _(max) (cm⁻¹): 3370.

EXAMPLE 12 Production of the nitrophenol (VII: X=Br)

2-Bromo-4-fluorophenol (28 g) was added to a solution of sodium hydroxide (7 g) in water (100 ml), and methyl chloroformate was dropwise added thereto at a temperature below 10° C. Precipitated crystals were collected by filtration and washed with water to give methyl (2-bromo-4-fluorophenyl) formate (41 g). M.P., 80.7° C.

The thus obtained methyl (2-bromo-4-fluorophenyl)-formate was suspended in conc. sulfuric acid (13 ml). To the suspension, a mixture of conc. sulfuric acid (13 ml) and conc. nitric acid (13 ml) was added at about 30° C. The mixture was stirred for 30 minutes and poured onto ice. Precipitated crystals were thoroughly washed with water, whereby yellow crystals of methyl (2-bromo-4-fluoro-5-nitrophenyl) formate (38.3 g) were obtained. M.P., 63.5°-64.5° C.

The product thus obtained was refluxed together with sodium hydroxide (6.2 g) and water (100 ml) for 3 hours. Insoluble materials were filtered, and the filtrate was acidified with hydrochloric acid. Precipitated crystals were collected by filtration and washed with water to obtain 25 g of 2-bromo-4-fluoro-5-nitrophenol. M.P., 126°-127° C.

NMR (CDCl₃, D₆ -DMSO) δ (ppm): 7.42 (1H, d, J=10Hz), 7.65 (1H, d, J=6Hz).

IRν^(nujol) _(max) (cm⁻¹): 3450.

EXAMPLE 13 Production of the aminophenol (IX: X=Cl)

A suspension of 2-chloro-4-fluoro-5-nitrophenol (9.17 g) and platinum dioxide (500 mg) in ethanol (120 ml) was subjected to catalytic reduction with hydrogen at room temperature and atmospheric pressure until a designed amount of hydrogen was absorbed. The catalyst was removed by filtration, and the filtrate was concentrated. The residue was extracted with ether, and the ether layer was concentrated to obtain 6.6 g of 3-amino-6-chloro-4-fluorophenol. M.P., 145°-146° C. (decomp.).

NMR (CDCl₃, D₆ -DMSO) δ (ppm): 6.4 (1 H, d, J=8Hz), 6.85 (1H, d, J=11Hz).

IR ν^(nujol) _(max) (cm⁻¹): 3400, 3320.

EXAMPLE 14 Production of the aminophenol (IX: X=Br)

In the same manner as above but using 2-bromo-4-fluoro-5-nitrophenol in place of 2-chloro-4-fluoro-5-nitrophenol, there was produced 3-amino-6-bromo-4-fluorophenol. M.P., 129°-130.5° C. (decomp.).

NMR (CDCl₃, D₆ -DMSO) δ (ppm): 6.57 (1H, d, J=8Hz), 7.1 (1H, d, J=11Hz).

IR ν^(nujol) _(max) (cm⁻¹): 3400, 3320.

In the practical usage of the tetrahydrophthalimides (I), they may be applied in any composition form such as emulsifiable concentrates, wettable powders, suspensions, granules or dusts.

The concentration of the active ingredient in such composition is usually within a range of 0.1 to 95% by weight, preferably of 1 to 80% by weight.

In the formulation of those compositions, a solid or liquid carrier or diluent may be used. As the solid carrier or diluent, there may be employed fine dust or granules of kaolin clay, attapulgite clay, bentonite, terra alba, pyrophyllite, talc, diatomaceous earth, calcite, walnut powder, urea, ammonium sulfate, synthetic hydrated silicon dioxide, etc. As the liquid carrier or diluent, there may be employed aromatic hydrocarbons (e.g. xylene, methylnaphthalene), alcohols (e.g. isopropanol, ethylene glycol, cellosolve), ketones (e.g. acetone, cyclohexanone, isophorone), plant oils (e.g. soybean oil, cottonseed oil), dimethyl sulfoxide, acetonitrile, water, etc.

A surface active agent used for emulsification, dispersion or spreading may be any of the non-ionic, anionic, cationic and amphoteric type of agents. Examples of the surface active agent include alkylsulfates, alkylaryl sulfonates, dialkylsuccinates, polyoxyethylene alkylaryl phosphates, polyoxyethylene alkyl ethers, polyoxyethylene alkylaryl ethers, polyoxyethylene-polyoxypropylene blocked polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene resin acid esters, abietic acid, dinaphthylmethanedisulfonates, paraffin and the like. If necessary, ligninsulfonates, alginates, polyvinyl alcohol, gum arabic, CMC (carboxymethylcellulose), PAP (isopropyl acid phosphate) or the like may be used as an auxiliary agent.

Practical embodiments of the herbicidal composition according to the invention are illustratively shown in the following examples wherein part(s) and % are by weight. The compound number of the active ingredient corresponds to those shown in Table 1.

FORMULATION EXAMPLE 1

Eighty parts of Compound No. 1, 12, 26, 35 or 47, 5 parts of polyoxyethylene alklaryl ether and 15 parts of synthetic hydrated silicon dioxide are well mixed while being powdered to obtain a wettable powder.

FORMULATION EXAMPLE 2

Ten parts of Compound No. 2, 8, 14, 22, 32 or 45, 7 parts of polyoxyethylene alkylaryl ether, 3 parts of alkylarylsulfonate and 80 parts of cyclohexanone are well mixed while being powdered to obtain an emulsifiable concentrate.

FORMULATION EXAMPLE 3

One part of Compound No. 1, 12, 23, 26, 35 or 44, 1 part of synthetic hydrated silicon dioxide, 5 parts of ligninsulfonate and 93 parts of kaolin clay are well mixed while being powdered. The mixture is then kneaded with water, granulated and dried to obtain a granule.

FORMULATION EXAMPLE 4

Three parts of Compound No. 1, 30, 31, 44 or 63, 0.5 part of isopropyl acid phosphate, 66.5 parts of kaolin clay and 30 parts of talc are well mixed while being powdered to obtain a dust.

FORMULATION EXAMPLE 5

Twenty parts of Compound No. 2, 13, 17, 25, 33 or 47 is mixed with 60 parts of an aqueous solution containing 3% of polyoxyethylene sorbitan monooleate and pulverized until the particle size of the active ingredient becomes less than 3 microns. Twenty parts of an aqueous solution containing 3% of sodium alginate as a dispersing agent are incorporated therein to obtain a suspension.

FORMULATION EXAMPLE 6

Fifty parts of Compound No. 67 or 84, 3 parts of calcium ligninsulfonate, 2 parts of sodium laurylsulfate and 45 parts of synthetic hydrated silicon dioxide are well mixed while being powdered to obtain a wettable powder.

FORMULATION EXAMPLE 7

Ten parts of Compound No. 68 or 81, 14 parts of polyoxyethylene styrylphenyl ether, 6 parts of calcium dodecylbenzenesulfonate, 30 parts of xylene and 40 parts of cyclohexanone are well mixed while being powdered to obtain an emulsifiable concentrate.

FORMULATION EXAMPLE 8

Two parts of Compound No. 75 or 85, 1 part of synthetic hydrated silicon dioxide, 2 parts of calcium ligninsulfonate, 30 parts of bentonite and 65 parts of kaolin clay are well mixed while being powdered. The mixture is then kneaded with water, granulated and dried to obtain a granule.

FORMULATION EXAMPLE 9

Twenty-five parts of Compound No. 71 or 84, 3 parts of polyoxyethylene sorbitan monooleate, 3 parts of carboxymethyl cellulose and 69 parts of water are well mixed and pulverized until the particle size of the active ingredient becomes less than 5 microns to obtain a granule.

These compositions comprising the tetrahydrophthalimides (I) may be applied as such, or after dilution with water, to the weeds in suitable application modes such as spraying, perfusion, etc. For instance, they may be spread over, perfused into or admixed with soil. Further, for instance, they may be applied for foliar treatment. If necessary, they may be used together with other herbicides to improve their activity as herbicides, and in some cases, a synergistic effect can be expected. They may be also applied in combination with insecticides, acaricides, nematocides, fungicides, plant growth regulators, fertilizers, soil controlling agents, etc.

The dosage rate of the tetrahydrophthalimide (I) as the active ingredient may be generally from 0.01 to 100 grams, preferably from 0.1 to 50 grams, per are. In the practical usage of the tetrahydrophthalimide (I) as emulsifiable concentrates, wettable powders or suspensions, it may be diluted with 1 to 10 liters of water (optionally including an auxiliary agent such as a spreading agent) per are. When formulated into granules or dust, it may be used as such without dilution.

The application of the tetrahydrophthalimides (I) as herbicides will be illustratively shown in the following Examples wherein the phytotoxicity to cultivated plants and the herbicidal activity on weeds were evaluated as follows: the aerial parts of the test plants were cut off and weighed (fresh weight); the percentage of the fresh weight of the treated plant to that of the untreated plant was calculated with the latter fresh weight taken as 100; and the phytotoxicity and the herbicidal activity were evaluated by the standard given in the table below.

    ______________________________________                                                    Fresh weight                                                        Rating     (percentage to untreated plot) (%)                                  value      Herbicidal activity                                                                             Phytotoxicity                                      ______________________________________                                         0          91-              91-                                                1          71-90            71-90                                              2          41-70            51-70                                              3          11-40            31-50                                              4          1-10             11-30                                              5          0                0-10                                               ______________________________________                                    

The following compounds were used in the Examples for comparison:

    __________________________________________________________________________     Compound No.                                                                           Structure                  Remarks                                     __________________________________________________________________________     (a)                                                                                     ##STR53##                 U.S. Pat. No. 4,032,326                     (b)                                                                                     ##STR54##                 U.S. Pat. No. 3,984,435                     (c)                                                                                     ##STR55##                 EP 0049508A                                 (d)                                                                                     ##STR56##                 Commercially available herbicide known                                         as "2,4,5-T" (Na salt)                      (e)                                                                                     ##STR57##                 Commercially available herbicide known                                         as "Bentazone" (Na salt)                    (f)                                                                                     ##STR58##                 Commercially available herbicide known                                         as "Atrazine"                               (g)                                                                                     ##STR59##                 Commercially available herbicide known                                         as "Metribuzin"                             (h)                                                                                     ##STR60##                 Commercially available herbicide known                                         as "Acifluorfen-sodium"                     __________________________________________________________________________

TEST EXAMPLE 1

Trays (33×23 cm²) were filled with upland field soil, and the seeds of soybean, tall morningglory, velvetleaf, black nightshade, cocklebur and hemp sesbania were sowed therein and grown for 18 days in a greenhouse. A designed amount of the test compound formulated into an emulsifiable concentrate and diluted with water was sprayed to the foliage of the test plants over the top by means of a small hand sprayer at a spray volume of 10 liters per are. At the time of application, the test plants were generally at the 2 to 4 leaf stage and had a height of 2 to 12 cm. Twenty days thereafter, herbicidal activity and phytotoxicity were examined. The results are shown in Table 2.

                                      TABLE 2                                      __________________________________________________________________________     Dosage                                                                         (weight of       Herbicidal activity                                                 active                                                                               Phyto-                                                                              Tall      Black                                               Compound                                                                             ingredient,                                                                          toxicity                                                                            morning-                                                                            Velvet-                                                                             night-    Hemp                                      No.   g/are)                                                                               Soybean                                                                             glory                                                                               leaf shade                                                                              Cocklebur                                                                            sesbania                                  __________________________________________________________________________     1     0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         2     0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         3     0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         4     0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         5     0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         6     0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         7     0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         8     0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   4     5                                         9     0.8   1    5    5    5   5     5                                               0.4   0    5    5    5   5     5                                         10    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         11    0.8   0    5    5    5   5     5                                               0.4   0    5    5    5   4     4                                         12    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   4     5                                         13    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         14    0.4   0    5    5    5   5     5                                               0.2   0    4    5    5   4     5                                         15    0.4   1    5    5    5   5     5                                               0.2   1    5    5    5   5     5                                         16    0.4   1    5    5    5   5     5                                               0.2   1    5    5    5   5     5                                         17    0.4   --   5    5    5   5     5                                               0.2   1    4    5    5   5     4                                         18    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         19    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         20    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         21    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         22    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   4     5                                         23    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   4     5                                         24    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         25    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   4     4                                         26    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         27    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         28    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         29    0.63  1    5    5    5   5     5                                               0.16  0    4    5    5   4     5                                         30    0.63  0    5    5    5   5     5                                               0.16  0    5    5    5   5     5                                         31    0.63  0    5    5    5   5     5                                               0.16  0    5    5    5   4     5                                         32    0.63  1    5    5    5   5     5                                               0.16  0    5    5    5   4     4                                         33    0.63  1    5    5    5   5     5                                               0.16  0    4    5    5   5     5                                         34    0.63  --   5    5    5   5     5                                               0.16  0    4    5    5   4     5                                         35    0.63  0    5    5    5   5     5                                               0.16  0    4    5    5   4     5                                         36    0.63  0    5    5    5   5     5                                               0.16  0    5    5    5   4     5                                         37    0.63  0    5    5    5   5     5                                               0.16  0    5    5    5   5     5                                         38    0.63  0    5    5    5   5     5                                               0.16  0    5    5    5   4     5                                         39    0.63  --   5    5    5   5     5                                               0.16  0    5    5    5   5     5                                         40    0.63  1    5    5    5   5     5                                               0.16  0    4    5    5   4     5                                         41    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     4                                         42    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     4                                         43    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         44    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         45    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         46    0.4   1    5    5    5   5     5                                               0.2   1    5    5    5   4     4                                         47    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     4                                         48    0.4   --   5    5    5   5     5                                               0.2   1    5    5    5   5     5                                         49    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   4     5                                         50    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         51    0.4   1    5    5    5   5     5                                               0.2   1    5    5    5   5     5                                         52    0.4   --   5    5    5   5     5                                               0.2   1    5    5    5   5     5                                         53    0.4   --   5    5    5   5     5                                               0.2   1    5    5    5   4     5                                         54    0.4   1    5    5    5   5     5                                               0.2   1    4    5    5   4     4                                         55    0.4   --   5    5    5   5     5                                               0.2   1    5    5    5   4     5                                         56    0.4   1    5    5    5   5     5                                               0.2   1    5    5    5   5     5                                         57    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   4     4                                         58    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   4     4                                         59    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         60    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         61    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         62    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         63    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     5                                         64    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   4     5                                         65    0.63  1    5    5    5   5     5                                               0.16  0    4    5    5   5     5                                         66    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   5     4                                         67    1.25  --   5    5    5   5     5                                               0.32  1    5    5    5   5     4                                         68    0.4   --   5    5    5   5     5                                               0.2   1    5    5    5   4     4                                         69    0.4   1    5    5    5   5     5                                               0.2   1    5    5    5   5     4                                         70    1.25  1    5    5    5   5     5                                               0.32  0    5    5    4   5     5                                         71    1.25  1    5    5    5   5     5                                               0.32  1    5    5    5   5     5                                         72    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   4     4                                         73    0.4   1    5    5    5   5     5                                               0.2   0    4    5    5   4     4                                         74    0.4   1    5    5    5   5     5                                               0.2   0    4    5    5   4     5                                         75    1.25  1    5    5    5   5     5                                               0.32  0    5    5    5   5     5                                         76    1.25  1    5    5    5   5     5                                               0.32  0    5    5    5   5     5                                         77    0.4   0    5    5    5   5     5                                               0.2   0    5    5    5   4     5                                         78    0.4   2    5    5    5   5     5                                               0.2   1    4    5    5   4     5                                         79    0.4   2    5    5    5   5     5                                               0.2   1    5    5    5   4     4                                         80    0.4   2    5    5    5   5     5                                               0.2   0    4    5    5   3     5                                         81    0.4   1    5    5    5   5     5                                               0.2   1    5    5    5   4     5                                         82    0.4   1    5    5    5   5     5                                               0.2   1    4    5    5   3     4                                         83    0.4   2    5    5    5   5     5                                               0.2   0    4    5    5   4     4                                         84    0.4   1    5    5    5   5     5                                               0.2   1    5    5    5   4     5                                         85    0.4   1    5    5    5   5     5                                               0.2   1    4    5    5   5     5                                         86    0.4   2    5    5    5   5     5                                               0.2   0    4    5    5   3     4                                         87    0.4   1    5    5    5   5     5                                               0.2   1    4    5    5   4     5                                         88    0.4   2    5    5    5   5     5                                               0.2   1    4    5    5   5     5                                         89    0.4   2    5    5    5   5     5                                               0.2   1    5    5    5   4     4                                         90    0.4   2    5    5    5   5     5                                               0.2   1    4    5    5   3     4                                         91    0.4   2    5    5    5   5     5                                               0.2   1    5    5    5   4     5                                         92    0.8   2    5    5    5   5     5                                               0.4   1    4    5    5   3     5                                         93    0.4   1    5    5    5   5     5                                               0.2   0    5    5    5   4     5                                         (a)   0.4   3    4    5    4   3     2                                               0.2   1    2    4    3   1     1                                         (b)   0.4   0    1    4    1   0     2                                         (c)   0.4   1    1    5    2   0     2                                         (d)   0.4   2    2    2    1   0     3                                         (h)   2.5   2    5    2    4   4     5                                               0.63  0    3    0    1   1     5                                         __________________________________________________________________________

TEST EXAMPLE 2

Wagner's pots (1/5000 are) were filled with field soil, and the seeds of tall morningglory, velvetleaf, redroot pigweed, soybean and corn were sowed therein and covered with soil to a depth of 1 cm. A designed amount of the test compound formulated into an emulsifiable concentrate and diluted with water was sprayed to the soil surface at a spray volume of 10 liters per are. The test plants were grown outdoors for 3 weeks, and herbicidal activity and phytotoxicity were examined. The results are shown in Table 3.

                  TABLE 3                                                          ______________________________________                                         Dosage                                                                         (weight of  Herbicidal activity                                                                               Phyto-                                          Com-  active in-                                                                               Tall                 toxicity                                  pound gredient, morning- Velvet-                                                                               Redroot                                                                               Soy-                                    No.   g/are)    glory    leaf   pigweed                                                                               bean Corn                               ______________________________________                                         1     20        5        5      5      0    0                                        10        5        5      5      0    0                                  2     10        5        5      5      0    0                                        5         5        5      5      0    0                                  13    10        5        5      5      0    0                                        5         5        5      5      0    0                                  14    10        5        5      5      0    0                                        5         5        5      5      0    0                                  15    10        5        5      5      0    0                                        5         5        5      5      0    0                                  22    10        5        5      5      0    0                                        5         5        5      5      0    0                                  24    10        5        5      5      0    0                                        5         5        5      5      0    0                                  26    10        5        5      5      0    0                                        5         5        5      5      0    0                                  29    10        5        5      5      0    0                                        5         5        5      5      0    0                                  30    10        5        5      5      0    0                                        5         5        5      5      0    0                                  31    10        5        5      5      0    0                                        5         5        5      5      0    0                                  32    10        5        5      5      0    0                                        5         5        5      5      0    0                                  34    10        5        5      5      0    0                                        5         5        5      5      0    0                                  35    10        5        5      5      0    0                                        5         5        5      5      0    0                                  44    20        5        5      5      0    0                                        10        5        5      5      0    0                                  45    20        5        5      5      0    0                                        10        5        5      5      0    0                                  47    10        5        5      5      0    0                                        5         5        5      5      0    0                                  48    0         5        5      5      0    0                                        10        5        5      5      0    0                                  49    10        5        5      5      0    0                                        5         5        5      5      0    0                                  51    10        5        5      5      0    0                                        5         5        5      5      0    0                                  52    10        5        5      5      0    0                                        5         5        5      5      0    0                                  57    10        5        5      5      0    0                                        5         5        5      5      0    0                                  63    10        5        5      5      0    0                                        5         5        5      5      0    0                                  64    10        5        5      5      0    0                                        5         5        5      5      0    0                                  ______________________________________                                    

TEST EXAMPLE 3

Plastic pots (diameter, 10 cm; height, 10 cm) were filled with upland field soil, and the seeds of soybean, cotton, tall morningglory and velvetleaf were sowed therein and covered with soil. A designed amount of the test compound formulated into an emulsifiable concentrate and diluted with water was sprayed to the soil at a spray volume of 10 liters per are and then the soil was well mixed to a depth of 4 cm. The test plants were further grown for 20 days in a greenhouse, and herbicidal activity and phytotoxicity were examined. The results are shown in Table 4.

                  TABLE 4                                                          ______________________________________                                                Dosage                                                                         (weight of                Phyto-                                        Com-   active in-                                                                               Herbicidal activity                                                                            toxicity                                      pound  gredient, Tall morning-                                                                             Velvet-                                                                               Soy-                                        No.    g/are)    glory      leaf   bean  Cotton                                ______________________________________                                         67     20        5          5      0     2                                            5         5          5      0     0                                     68     20        5          5      0     1                                            5         4          5      0     0                                     69     20        5          5      0     2                                            5         5          5      0     0                                     70     20        5          5      0     0                                     71     20        5          5      0     2                                            5         5          5      0     1                                     72     20        5          5      0     0                                     73     20        5          5      0     0                                     74     20        5          5      0     0                                     75     20        5          5      0     2                                            5         5          5      0     0                                     76     20        5          5      0     0                                     77     20        5          5      0     0                                     78     20        5          5      0     1                                     89     20        5          5      0     2                                     91     20        5          5      0     1                                     92     20        5          5      0     0                                     93     20        5          5      0     1                                            5         5          5      0     0                                     ______________________________________                                    

TEST EXAMPLE 4

Plastic pots (diameter, 8 cm; height, 12 cm) filled with paddy field soil, and the seeds of barnyardgrass and broad-leaved weeds (e.g. false pimpernel, toothcup, waterwort) were sowed therein to a depth of 1 to 2 cm. The pots were placed under a flooded condition, and the tubers of arrowhead and the rice seedlings of the 2-leaf stage were transplanted therein at a depth of 1 to 2 cm and grown for 6 days in a greenhouse. A designed amount of the test compound formulated into an emulsifiable concentrate and diluted with water was perfused into the pots at a perfusion volume of 5 ml per pot. The test plants were further grown for 20 days in the greenhouse, and phytotoxicity and herbicidal activity were examined. The results are shown in Table 5.

                  TABLE 5                                                          ______________________________________                                         Dosage                                                                         (weight of   Herbicidal activity Phyto-                                        Com-   active in-          Broad-        toxicity                              pound  gredient, Barnyard- leaved Arrow- Rice                                  No.    g/are)    glass     weed   head   plant                                 ______________________________________                                         26     5         4         5      4      1                                     44     5         3         5      5      1                                     48     5         3         5      4      1                                     51     5         4         5      5      1                                     67     10        5         5      4      1                                     68     10        4         5      5      0                                     71     10        5         5      5      1                                     75     10        5         5      5      1                                     89     10        4         5      5      0                                     91     10        5         5      5      1                                     93     10        4         5      4      0                                     ______________________________________                                    

TEST EXAMPLE 5

The seeds of soybean, cocklebur, tall morningglory, velvetleaf, jimson weed, redroot pigweed, sunflower, common ragweed and common lambsquarters were sowed in the field as previously laid up in ridges, each ridge being plotted in 3 m². When soybean, cocklebur and other plants were grown at the 1-2 compound leaf stage, 6-leaf stage and 4-9 leaf stage, respectively, a designed amount of the test compound formulated into an emulsifiable concentrate and diluted with water (including a spreading agent) was sprayed to the foliage of the test plants by means of a small hand sprayer at a spray volume of 5 liters per are with three replications. Thirty days thereafter, herbicidal activity and phytotoxicity were examined. The results are shown in Table 6.

                                      TABLE 6                                      __________________________________________________________________________     Dosage                                                                         (weight of    Herbicidal activity                                              Com-                                                                               active in-                                                                           Phyto-  Tall                   Common                                                                              Common                           pound                                                                              gredient,                                                                            toxicity                                                                           Cock-                                                                              morning-                                                                            Velvet-                                                                             Jimson                                                                             Redroot                                                                             Sun-                                                                               rag- lambs-                           No. g/are)                                                                               Soybean                                                                            lebur                                                                              glory                                                                               leaf weed                                                                               pigweed                                                                             flower                                                                             weed quarters                         __________________________________________________________________________     1   1     1   5   5    5    5   5    5   5    5                                    0.5   1   4   5    5    5   5    5   5    5                                8   1     1   5   5    5    5   5    5   5    5                                    0.5   0   5   5    5    5   5    5   5    5                                13  1     1   5   5    5    5   5    5   5    5                                    0.5   0   5   5    5    5   5    5   5    4                                30  1     1   5   5    5    5   5    5   5    5                                    0.5   0   4   5    5    5   5    4   5    5                                (e) 10    1   5   3    5    5   2    5   5    5                                    5     0   5   1    5    5   0    5   5    3                                __________________________________________________________________________

TEST EXAMPLE 6

The seeds of corn, cocklebur, tall morningglory, velvetleaf, jimson weed and redroot pigweed were sowed in the field as previously laid up in ridges, each ridge being plotted in 3 m². When corn, cocklebur and other plants were grown at the 6-7 leaf stage, 4-leaf stage and 3-6 leaf stage, respectively, a designed amount of the test compound formulated into an emulsifiable concentrate and diluted with water (including a spreading agent) was sprayed to the foliage of the test plants by means of a small hand sprayer at a spray volume of 5 liters per are with three replications. Thirty days thereafter, herbicidal activity and phytotoxicity were examined. The results are shown in Table 7.

                                      TABLE 7                                      __________________________________________________________________________     Dosage                                                                         (weight of      Herbicidal activity                                                  active in-                                                                           Phyto-    Tall                                                     Compound                                                                             gredient,                                                                            toxicity  morning-                                                                            Velvet-                                                                            Jimson                                                                             Redroot                                     No.   g/are)                                                                               Corn                                                                               Cocklebur                                                                            glory                                                                               leaf                                                                               weed                                                                               pigweed                                     __________________________________________________________________________     1     1     1   5     5    5   5   5                                                 0.5   0   5     5    5   5   5                                           8     1     1   5     5    5   5   5                                                 0.5   1   4     5    5   5   5                                           (f)   10    1   5     5    5   5   5                                                 5     0   5     4    4   5   4                                           __________________________________________________________________________

TEST EXAMPLE 7

Seeds of soybean, tall morningglory, velvetleaf, common lambsquarters, redroot pigweed, black nightshade, common ragweed and common purslane were sowed in the field as previously laid up in ridges, each ridge being plotted in 3 m². A designed amount of the test compound formulated into an emulsifiable concentrate and diluted with water (including a spreading agent) was sprayed to the soil surface by means of a small hand sprayer at a spray volume of 5 liters per are with three replications. Thirty days thereafter, herbicidal activity and phytotoxicity were examined. The results are shown in Table 8.

                                      TABLE 8                                      __________________________________________________________________________     Dosage                                                                         (weight of      Herbicidal activity                                            Com-                                                                               active in-                                                                           Phyto-                                                                               Tall      Common    Black                                                                              Common                                 pound                                                                              gredient,                                                                            toxicity                                                                             morning-                                                                            Velvet-                                                                             lambs-                                                                              Redroot                                                                             night-                                                                             rag- Common                            No. g/are)                                                                               Soybean                                                                              glory                                                                               leaf quarters                                                                            pigweed                                                                             shade                                                                              weed purslane                          __________________________________________________________________________     13  16    0     5    5    5    5    5   5    5                                     8     0     4    5    5    5    5   4    5                                 (g) 8     1     3    5    5    5    3   5    5                                     4     0     1    4    4    5    1   4    5                                 __________________________________________________________________________ 

What is claimed is:
 1. A compound of the formula: ##STR61## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkyl or lower alkoxy, X is chlorine or bromine, Y is oxygen or imino and Z is oxygen or sulfur.
 2. A herbicidal composition which comprises a herbicidally effective amount of a compound of the formula: ##STR62## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkyl or lower alkoxy, X is chlorine or bromine, Y is oxygen or imino and Z is oxygen or sulfur as an active ingredient and an inert carrier.
 3. A method for controlling or exterminating weeds in a field which comprises applying, to an area where weeds grow, a herbicidally effective amount of a compound of the formula: ##STR63## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkyl or lower alkoxy, X is chlorine or bromine, Y is oxygen or imino and Z is oxygen or sulfur as an active ingredient and an inert carrier.
 4. A compound of the formula: ##STR64## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkyl or lower alkoxy, X is chlorine or bromine, Y is oxygen and Z is oxygen or sulfur.
 5. A herbicidal composition which comprises a herbicidally effective amount of a compound of the formula: ##STR65## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkyl or lower alkoxy, X is chlorine or bromine, Y is oxygen and Z is oxygen or sulfur as an active ingredient and an inert carrier.
 6. A method for controlling or exterminating weeds in a field which comprises applying, to an area where weeds grow, a herbicidally effective amount of a compound of the formula: ##STR66## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkyl or lower alkoxy, X is chlorine or bromine, Y is oxygen and Z is oxygen or sulfur as an active ingredient and an inert carrier.
 7. A compound of the formula: ##STR67## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkoxy, X is chlorine or bromine, Y is imino and Z is oxygen or sulfur.
 8. A herbicidal composition which comprises a herbicidally effective amount of a compound of the formula: ##STR68## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkoxy, X is chlorine or bromine, Y is imino and Z is oxygen or sulfur as an active ingredient and an inert carrier.
 9. A method for controlling or exterminating weeds in a field which comprises applying, to an area where weeds grow, a herbicidally effective amount of a compound of the formula: ##STR69## wherein R₁ is hydrogen, alkyl, lower cycloalkyl, lower alkyl(lower)cycloalkyl, lower cycloalkyl(lower)alkyl, lower alkoxy(lower)alkyl, lower alkenyl, lower cycloalkenyl, lower cycloalkenyl(lower)alkyl, phenyl, cyano(lower)alkyl, lower alkynyl, lower alkylideneamino, lower alkylthio(lower)alkyl, benzyl, halo(lower)alkyl or lower cycloalkylideneamino, R₂ is lower alkoxy, X is chlorine or bromine, Y is imino and Z is oxygen or sulfur as an active ingredient and an inert carrier.
 10. The compound according to claim 4, wherein R₂ is lower alkoxy.
 11. The compound according to claim 4, wherein R₂ is lower alkoxy and Z is oxygen.
 12. The composition according to claim 2, wherein R₂ is lower alkoxy.
 13. The composition according to claim 2, wherein R₂ is lower alkoxy and Z is oxygen.
 14. The method according to claim 3, wherein R₂ is lower alkoxy.
 15. The method according to claim 3, wherein R₂ is lower alkoxy and Z is oxygen.
 16. The method according to claim 6, wherein said compound is applied by post-emergence treatment.
 17. The method according to claim 16, wherein said dosage is from 0.1 to 1.25 grams per are.
 18. The method according to claim 16, wherein said dosage is from 0.1 to 0.8 grams per are.
 19. The method according to claim 16, wherein said dosage is from 0.2 to 0.4 grams per are.
 20. The method according to claim 16, wherein the field is a soybean field.
 21. The method according to claim 17, wherein the field is a soybean field.
 22. The method according to claim 18, wherein the field is a soybean field.
 23. The method according to claim 19, wherein the field is a soybean field.
 24. The compound according to claim 7, wherein Z is oxygen.
 25. The composition according to claim 8, wherein Z is oxygen.
 26. The method according to claim 9, wherein Z is oxygen.
 27. The method according to claim 9, wherein said compound is applied by post-emergence treatment.
 28. The method according to claim 27, wherein said dosage is from 0.1 to 1.25 grams per are.
 29. The method according to claim 27, wherein said dosage is from 0.1 to 0.8 grams per are.
 30. The method according to claim 27, wherein said dosage is from 0.2 to 0.4 grams per are.
 31. The method according to claim 27, wherein the field is a soybean field.
 32. The method according to claim 28, wherein the field is a soybean field.
 33. The method according to claim 29, wherein the field is a soybean field.
 34. The method according to claim 30, wherein the field is a soybean field.
 35. The compound according to claim 1, wherein Y is imino.
 36. The compound according to claim 1, which is 2-(4-Chloro-2-fluoro-5-1-(methoxycarbonyl)-ethylaminophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 37. The compound according to claim 1, which is 2-(4-Bromo-2-fluoro-5-1-(methoxycarbonyl)-ethylaminophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 38. The compound according to claim 1, which is 2-(4-Bromo-2-fluoro-5-cyclopentyloxycarbonyl(methoxy)methylaminophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 39. The composition according to claim 2, wherein Y is imino.
 40. The composition according to claim 2, wherein the compound is 2-(4-chloro-2-fluoro-5-1-(methoxycarbonyl)ethylaminophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 41. The composition according to claim 2, wherein the compound is 2-(4-bromo-2-fluoro-5-1-(methoxycarbonyl)ethylaminophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 42. The composition according to claim 2, wherein the compound is 2-(4-bromo-2-fluoro-5-cyclopentyloxycarbonyl(methoxy)methylaminophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 43. The method according to claim 3, wherein the compound is 2-(4-chloro-2-fluoro-5-1-(methoxycarbonyl)ethylamino phenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 44. The method according to claim 3, wherein the compound is 2-(4-bromo-2-fluoro-5-1-(methoxycarbonyl)ethylaminophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 45. The method according to claim 3, wherein the compound is 2-(4-bromo-2-fluoro-5-cyclopentyloxycarbonyl(methoxy)methylaminophenyl)-4,5,6,7-tetrahydro-2H-isoindole-1,3-dione.
 46. The method according to claim 3, wherein said compound is applied by post-emergence treatment.
 47. The method according to claim 46, wherein said dosage is from 0.1 to 1.25 grams per are.
 48. The method according to claim 46, wherein said dosage is from 0.1 to 0.8 grams per are.
 49. The method according to claim 46, wherein said dosage is from 0.2 to 0.4 grams per are.
 50. The method according to claim 46, wherein the field is a soybean field.
 51. The method according to claim 47, wherein the field is a soybean field.
 52. The method according to claim 48, wherein the field is a soybean field.
 53. The method according to claim 49, wherein the field is a soybean field. 